What was found
DURING CRUISE ALTITUDE, THE RT FUEL GUAGE READ 700 LBS LESS THAN THE LT FUEL GUAGE, EVEN THOUGH CENTER TANK FUEL WAS BURNED FOR THE FIRST HOUR OF FLIGHT AT ENGINE SHUTDOWN, THE IMBALANCE IS 4.07 / 3.42. THE FUEL BURN FOR BOTH ENGINES WAS THE SAME. MAINTENANCE ACCOMPLISHED FQIS BITE TEST WITH NO FAULTS FOUND. RAN FUEL PUMPS WITH VALVES CLOSED, FOUND NO APPARENT FUEL MIGRATION ON THE GROUND. NO HISTORY FOR THIS ISSUE. RETURNED TO SERVICE.